Rotary toothbrush



Dec. 15, 1953 D. P. GROVER 2,662,239

ROTARY TOOTHBRUSH Filed NOV. 9, 1946 FIG.l

Fasi 5' INVENTOR: `DONALD P @ROVER Patented Dec. l5, 1953 UNITED STATES PATENT OFFICE u' 2&662239.

ROTARY TO'OTHBRUSH Donaldl.t GroverChicagoIll. Application November 9, 1946, SerialINo. 708;877

lThis invention relates in general to power` operated toothbrushes and particularly to the ro,- tary type which may be used by individuals at homev as distinguished from those inA professional use by dentists.

In power driven toothbrushes ofthe rotary type heretofore known it has been customary to provide an electric motor embodiedv as apart of: the handle portion of the brush or other similar types of driving mechanism to rotate the brush element. The present invention contemplates,l as one advantagethereof, the use of, novel driving means primarily adapted to transmit an intermittent rotation to the brush element, but which can` easily be modified whereby a substantially constant rotation of the brush element may take. place.

Another advantage which the present invention, provides` over those heretofore; known is the `adaptability of the toothbrush for simultaneously massaging the gums as the teeth are bei-ng cleaned. The very nature` of the novel driving mechanism ci this invention will cause a slight vibration of the entireY device which can bey transmitted to a suitable gum massaging element for the purpose of massaging the gums.

I have disclosed in` my earlier led cao-pending applications, Ser. No. 691,273 iiledY August 17', 1946, now Patent No. 2,533,106, issued- December A5, 1950; Ser. No. 691,979 iiledV August 2'1,` 1946', now Patent No. 2,533,107 issued December 5, '19.50,' and Ser. No. 692,270 led August 22, 19,46, now Patent No. 2,533,108. issued December 5, 1950A certain novel and advantageous improvements in rotary toothbrushes in the form of lip guards for protecting the lip of a` user against irritation and laceration4 by the. rotating brush element. The basic reasons and advantages of such a protective means are. adequately set forth in said applications and it is to be understood that suitable forms of lip guards such as those disclosed therein are equally adapted for use in the present` invention.

I have also disclosed in my earlier filed cow pending applications bearing Ser. No. 700,315 iiled September 30, 1946. and Ser. No. 702,535.A filed October 10, 1946, various modified forms of toothbrushes having multiple heads or more than one brush element whereby the inner and outer sides of the teeth may be cleaned simultaneously.A The novel drive means disclosed herein may be, adapted for use in the type of rotary toothbrush disclosed in all of said applications as well as .in the single head type `illustrated herein.

One of the principal objects of the present invention is; toi provide a shank or handle portion for a rotary toothbrush which embodies a longitudinally reciprocablev shaft. for rotating the brush element, and.' novel driving means for reciprocating the:- shaft.

A stiliI furtherobjectof the invention is to pro- Vide; an rotary toothbrush with novel electrical means forv intermittently rotatingl the brush element. thereof.

Still another object is to. provide a rotary toothbrush whereinv novel electrical means are provided: forv longitudinally reciprocating a shaft Which: is; so connected' with the brush element thereof as to rotate, the, same during reciprocation of` the, shaft.,

Another and more specific object of the` in vention isto. provide a rotary toothbrush whercin the handle portion thereof contains a solenoid which may be intermittently energized and deenergized toI draw the armature thereof inwardly each time the`A solenoidA is energized thus reciprocating the arma-ture; Connecting means are also providedbetween the armature and brush ele-V ment whereby 'said reciprocating motion is. converted to a, rotary motion of the brush element.

Other objects. and advantages of the inven tion will become apparent upon reading the following description taken in connection with the accompanying drawingV in which:

Fig., 1 is; a longitudinal vertical sectional View through a, rotary' toothbrush embodying the fea. tures of: the: present invention;

Fig. 2f is an enlarged longitudinal vertical section through the shank'r of the toothbrush shown in Fig. 1;:

Fig. 3V is a fragmentaryv plan view, partly in SEQOH, of the brush, end of the shank shown in Fig. 4 is a vertical transverse section through the. shank taken substantially along the plane of, line. 4.--4 of Figf. 2;

Fig. 5 is a fragmentary perspectiveview of one end of the shank` shown in Fig. 2;

Fig. 6 is a, fragmentary' plan view of the brush end of the toothbrush showing a modified form of connecting meansv between the shaft and the brush element; and

Fig. 7 is a view similar to Fig. 6 but showing a still further modified form of connecting means for rotating, the brush. element.

While the present invention as disclosed here in illustrates the. use. of a single. reciprocating shaft forv rotating the. brush element, it will be understood that the use. of two or more such reciprocating shafts may be utilized if so desired without in any way departing from the spirit of the invention.

Referring now more particularly to the drawing and especially to Fig. 2, the toothbrush unit is composed of a shank portion indicated by the numeral I which has an elongated opening 2 extending throughout the length thereof and adapted to receive a shaft 3. Each end of the opening 2 is preferably provided with slightly enlarged portions 4 and 5 for the purpose of receiving the bearing members 6 and 1 within which the shaft 3 is adapted to longitudinally reciprocate. The forward end of the shank I terminates in a hollow shell-like portion comprising a shield 8 having the ends 3 and I0 thereof suitably constructed to removably receive the spindle Ii of the brush element I2. The specific form of mounting means for the brush element spindle forms no part of the present invention and may include any suitable type of supporting means such as those disclosed in my earlier filed co-pending application bearing Ser. No. 705,282 filed October 24, 1946.

As stated hereinbefore, any suitable form of lip guard may also be combined for use in the present invention such as those disclosed in any vof the ilrst three co-pending applications above referred to. The form of lip guard illustrated herein comprises a plurality of teeth or partitions I3 extending along one side of the shield 3 and preferably along that side toward which the brush element rotates so as to protect the lip of a user from being drawn inwardly against the bristles of the brush and between the bristles .and the edge of the shield. It will be evident that the brush element can be caused to rotate in the opposite direction from that shown, in which event the lip guard would be located on the opposite side of the shield.

The forward end of the shaft 3 is provided with actuating means in the form of a pawl I4 which is adapted to be in contact with the teeth of a ratchet wheel I5 mounted centrally of the spindle II. Thus it will be evident that longitudinal reciprocation of the shaft 3 will impart a rotary movement to the brush element I2 in a counterclockwise direction each time a forward movement of the shaft takes place. A stop member I6 may be suitably provided in the form of an elongated ringer to prevent rotation of the brush element in the opposite direction by bearing against the teeth of the ratchet wheel I5.

Adjacent the inner end of the shaft 3 it has an annular groove I1 within which a retaining ring I8 is located. to normally retain the shaft within the shank. A small pin I9 extends transversely through the shaft 3 and into slots 20 of the bearing 6. This construction will prevent a rotation of the shaft and yet will permit a longitudinal sliding movement thereof.

The inner end of the shank I is preferably enlarged slightly as at 2I and has an opening 22 in the end thereof. The end 23 of the shaft 3 extends into the opening 22 and is externally threaded for the purpose of threadedly receiving the end member 24 thereon. This end member 24 is provided with an annular rib 25 which may take the form of a ring or which may be integral with the member 24 and provides a bearing for one end of a coiled compression spring 26 surrounding the member 24. The other end of said spring bears against the shank at the inner end of the opening 22. This con` struction will maintain the shaft 3 normally in a retracted position away from the brush ele- 4 ment and in readiness for a sliding movement which will rotate the brush element.

The enlarged end 2l of the shank is preferably threaded as at 21 whereby it may be threadedly connected to the main handle portion 28. While many forms of driving means may be utilized to impart a reciprocating movement to the shaft 3, one of the forms illustrated herein comprises a solenoid 29 suitably located within the handle portion 28 and is adapted to receive a plunger or armature 30 for reciprocating movement therein. The outer end of the member 24 is preferably formed in the shape of a cone as indicated at 3I whereby it may be received within a complementary opening or recess in one end of the armature 3U as shown in Fig. l. This will maintain the armature 30 and shaft 3 in substantial alignment and will also impart a reciprocating movement to the two members.

IThat is, a movement of the armature toward the brush end of the device when the solenoid is energized will urge the shaft 3 in the same direction to rotate the brush, and a movement in the opposite direction of the shaft 3, due to the action of the coiled spring 26, will also urge the armature 30 in that direction.

The solenoid may be energized by suitable conductors 32 and 33 carrying current from a source of electrical energy, and novel means are provided to intermittently open and close the circuit between these two wires from the high to the low sides of the line. One form which this means may take includes a contact 34 connected to the solenoid and which is adapted to have a spring switch blade 35 bear thereagainst, which blade is suitably secured within the handle portion to the conductor 33 by means of the fastening means 36. The conductor 32 is connected directly to the solenoid and will carry current through the Contact 34 and the spring switch blade 35 to the other side of the line through the conductor 33. The blade 35 constitutes a normally open switch which may be closed to complete the circuit through the soley noid by movement of the armature 3|) thereagainst.

The outer end of the armature is provided with a suitable nose 31 adapted to bear against the spring switch blade 35 and has an annular rib 38 thereon to limit the inward movement of the armature by bearing against one end of the solenoid.

In the normal position of the various parts, the spring 26 will urge the shaft 3 and armature 30 in a direction away from the brush end of the device as shown in Fig. l, whereupon the nose 31 of the armature bears against the spring switch blade 35 to normally close the circuit between the conductors 32 and 33. When these conductors are connected to a suitable source of electrical energy, such as the ordinary wall socket found in the home, electrical current will be carried through the solenoid, thus energizing the solenoid and drawing the armature 30 inwardly. The inward movement of the armature 3B will cause a forward movement of the shaft 3 tol rotate the brush element through the pawl and ratchet mechanism indicated at I4. and I5. As soon as the armature is moved in this direction, the spring switch blade 35 will be moved away from the contact 34 to break the circuit between the two sides of the line and deenergize the solenoid. As soon as the solenoid has become de-energized, the spring 26 will act to move the shaft 3 and armature 3U in a direction .away from the brushend of the device', whereupon the pawl I4 willbe in a positionior the next succeeding rotative movement 'of the brush element and the nose 31 of the armature will move the spring switch blade 35 against the contact 34 to again complete the circuit and energize the solenoid. As long as the conductors 32 and 33 are connected to a source of electrical energy, the above described action will take place continuously. The solenoid will be alternately energized and dea-.energized to thereby induce a rapid reciprocation of the armature 30 and the shaft 3 thus inducing a rapid intermittent rotation of the brush element l2.

It will be evident that two shafts and two solenoids could be used if desired in connection with two pawl and ratchet arrangements on the spindle Il, and if they are caused to reciprocate simultaneously in opposite directions, a substantially constant rotation of the brush element will take place instead of the intermittent one as explained above.

Fig. 6 illustrates a modified form of the invention Where, instead of the pawl and ratchet arrangement described above, an arcuate arm 39 extends transversely of the shank and is secured to the outer end of the shaft 3 at substantially its midpoint. In this form of the invention the ends of the arcuate member 3s are provided with the pavvls 40 and 4l adapted to be in engagement with the ratchets 42 and 43 located on each end of the spindle 44 of the brush element 45. The operation of this form of the invention is substantially the same as that described above and the arcuate member 39 is shown in its normal retracted position in full lines and its forward position in dotted lines. In the dotted line position thereof the pawls 40 and 4I will have rotated the ratchets 42 and 43 thereby causing a rotation of the brush element. The driving mechanism may be utilized with this modified form and will function in the same manner above described.

In Fig. 7 the arcuate member has been split and is divided into two portions 4E and 41 both of which are pivotally secured at their inner ends to the end of the shaft 3 by means of the pivot pin 48. The portion 46 is pivotally mounted at substantially its center by means of the pivot pin 49 to any suitable stationary part of the shank such as the shield 8. Likewise, the other portion 41 thereof may be pivotally mounted to the same member by means of the pivot pin i). In this form of the invention the rotation takes place when the shaft 3 is moved away from the brush end of the device, which is opposite to the functioning thereof explained with regard to the other forms. As the shaft 3 is caused to reciprocate longitudinally and moves away from the brush end of the device, the pivotal arrangement thereof will cause the outer ends of the portions 45 and 4'! to move forwardly and the pawls 40 and 4I mounted on said ends will thus rotate the ratchets 42 and 43 and the brush element 45.

As mentioned earlier herein, novel gum massaging means may be employed with this type of construction whereby the gums of a user may be massaged simultaneously with the cleaning of the teeth. Such a suitable gum massaging element is indicated by the numeral 5i and is adapted to be mounted on the forward or outer side of the shield 8. This element may, if desired, constitute an ordinary piece of rubber having the outer surface thereof roughened in any suitable manner. The rapid reciprocation of the shaft and armatureof the solenoid-will induce a certain amount of vibration tothe-entire device. This'vibration can be advantageously utilized through the gum massagingelement, which will also have imparted thereto a vibratory movement. When the teeth are being cleaned, the massaging elementA maybe placed against the gums thereof and while the rotating brush element is cleaning the teeth, the vibration of the massaging element will be massaging the gums. As in all of my earlier filed applications above referred to, the driving means is preferably arranged to rotate the brush element in a direction away from the gums, so that the cleaning will begin on or near the gums and will move toward the biting surface of the teeth.

From the foregoing description it will be evident that the invention disclosed herein embodies certain novel ideas in driving means for imparting a rotary movement to a power driven toothbrush. It will be clear that certain changes may be made in the form, construction and arrangement of parts from that disclosed herein without in any way departing from the spirit of the invention or sacrificing any of the attendant advantages thereof, provided, however, that such changes fall within the scope of the claims appended hereto.

Having thus described my invention what I claim as new and desire to secure by Letters Patent of the United States is:

l. A rotary toothbrush of the class described comprising a handle portion, a brush element rotatably mounted thereon, said brush element including an elongated spindle, a ratchet wheel on each end of said spindle, a pawl located adjacent each ratchet wheel, and means to move said pawls to thereby rotate said ratchet wheels and said brush element intermittently in one direction.

2. A rotary toothbrush of the class described comprising a handle portion, a brush element rotatably mounted thereon, said brush element including an elongated spindle, a ratchet wheel on said spindle, an elongated shaft located within said handle portion having an inner end and an outer end and extending longitudinally thereof, pawl means fixed to the outer end of said shaft, extending in the same direction as said shaft, and in contact with said ratchet wheel, and electrical means to reciprocate said shaft and pawl means longitudinally thereby to rotate said brush element upon each movement of said shaft in a direction toward its outer end.

3. A rotary toothbrush of the class described comprising a handle portion, a brush element rotatably mounted thereon, said brush element including an elongated spindle, a ratchet wheel on said spindle intermediate the ends thereof, an elongated shaft having an inner end and an outer end located within said handle portion and extending longitudinally thereof, pawl means fixed to the outer end of said shaft, extending in the same direction as said shaft, and in conr tact with said ratchet wheel, electrical means to reciprocate said shaft and pawl means longitudinally thereby to rotate said brush element upon each movement of said shaft in a direction toward its outer end, and a xed stop member mounted in said handle adjacent the outer end of said shaft and in contact with said ratchet wheel to prevent rotation of said ratchet wheel when said shaft is moved in the opposite direction.

DONALD P. GROVER.

(References on following page) 7 References Cited in the 111e of this patent Number UNITED STATES PATENTS Name Date Levin July 16, 1997 Davidson July 8, 1919 Pond Nov. 18, 1919 Vctorius J an. 6, 1925 Zave Mar. 30, 1926 Bryant May 24,. 1927 Sticht Feb. 26, 1929 Robey Feb. 10, 1931 Hawk Sept. 19, 1933 Carlson et al Feb. 27, 1934 Number 1 Number 

